UPDATE: My review of the mAT-705 ATU below is accurate as of its original posting. Since this review, however, I’ve discovered some design issues that prevent me from continuing to recommend it. Click here for details.
UPDATE 2: Mat-Tuner released the latest updated and upgraded version of the mAT-705 in December 2020. It’s called the mAT-705Plus. Click here to read my initial review of the mAT-705Plus. Note that the following article pertains to the original mAT-705 which is no no longer being produced, but still available for sale (at time of posting) both new and used.
Last week, Vibroplex sent me their new Mat-Tuner mAT-705 external ATU on loan to evaluate with my recently acquired Icom IC-705.
The new mAT-705 antenna tuner is designed specifically for use with the new Icom IC-705 QRP transceiver. Connect the mAT-705 directly to the TUNER jack on the IC-705 with the included cable and control the antenna tuner directly from the front panel of the radio or use RF-sensing to actuate the tuner when changing bands. 1.8-54 MHz, 5-1500 ohms matching range, 16000 user memories recalling previous used settings internal to the tuner when returning to an earlier used frequency.
The tuner is powered by an internal standard 9 volt alkaline battery. Power saving technology inside the tuner allows the use of the unit for months without replacement. No battery power is consumed by the unit when powered off.
Yesterday, I stopped by South Mountains State Game Land (K-6952) to give the mAT-705 some field time. Up to this point, I had not used the tuner other than tuning to the 80 and 40 meter bands from home (mainly to make sure it worked before hitting the field).
To really give the mAT-705 a workout, I deployed my CHA Emcomm III Portable random wire antenna. The Emcomm III is the only field antenna in my arsenal that covers 160 meters – 6 meters–an exceptionally wide frequency range.
What I like about this particular POTA site is the open parking area which allows me to configure the Emcomm III a number of ways.
The Emcomm III, being a wire antenna, is incredibly stealthy. Since you can’t see it in the photo above, I’ve marked up the configuration below (click to enlarge):
I’m guessing the apex of the antenna was easily 45′ high.
Activating
I started my activation on the 80 meter band.
After working a few stations on 80 meters, I decided to test the mAT-Tuner over a fairly wide frequency range before calling CQ on the 40 meter band.
Here’s a short video:
POTA Hunters: look for me on the 160 meter band this fall and winter! I’m so impressed how well it matched the Emcomm III on 160.
Indeed, I am very pleased with how quickly and efficiently the mAT-705 found matches on every band I tested.
In terms of form factor, the mAT-705 is quite compact, but a little longer in length than I had anticipated. Honestly, though, there’s nothing here to complain about.
The enclosure/chassis is incredibly strong. I’m willing to bet you could accidentally drive over it with your car and it would survive in tact.
The mAT is powered by an alkaline 9V battery. Vibroplex expects that this battery will last for months under normal use.
Note that there is a specific procedure for replacing the battery in order to protect the LED “illuminators” that are press-fit to the board.:
Remove the case by removing the 4 rear 2mm allen screws.
Turn the tuner upside down and shake it a little to get the PCB to slide out of the case enough to grab.
Carefully grasp the PCB sides and slide the board out slowly.
Update: I’ve followed the procedure above and still had an issue with the illuminators falling out. They really need to be secured better. I was able to re-insert them and close the ATU, but when you open the mAT-705 to change the battery, be in a space where you can capture both of them if they fall out.
Any mAT-705 negatives?
Not really, but I do feel the price is a little steep at $219.95–but then again the mAT-705 seems to do the job and do it well. I have to assume the TBA Icom AH-705 ATU will cost at least as much. I’m okay with paying at the top end of the market if I’m getting a quality product and this certainly seems like one.
I like the fact that the mAT-705 integrates perfectly with the IC-705 via the control cable and that I don’t have to worry about protecting it at all in my backpack. It’ll also take the IC-705 through the entire HF spectrum and even up to 6 meters.
I plan to continue using the mAT-705 for a while and even test it on severely non-resonant antennas just to see how far I can push it for a match.
Stay tuned! (See what I did there–?)
Many thanks to Vibroplex, again, for lending me this mAT-705 for review and evaluation.
I feel pretty lucky that my QTH borders tens of thousands of acres of protected lands: a watershed, Pisgah National Forest, and Pisgah Game Land WRC. Our family enjoys hiking, so we often venture into the forest around our house and explore the ridge lines, peaks, and views.
This year, while exploring all of the public lands available to activate in the Parks On The Air (POTA) program, I realized there were no less than two sites within a 30-35 minute hike of my home! Quite literally, in my back yard.
In fact, there’s a large area where two POTA entities overlap–Pisgah National Forest and Pisgah Game Land–giving me the opportunity to activate both sites simultaneously as a “two-fer.”
If it’s so close, you may wonder why I haven’t activated it yet–? Well, by the time I realized the park boundary overlap was within hiking distance of the house, we were well into spring, thus the forest was lush with vegetation and the hike to the site requires proper trail-blazing with an elevation change of 600′ (183M). It’s a much easier hike in fall and winter when you can actually see where you’re going through the trees.
Still: Saturday morning, the weather was so perfect for hiking I floated the idea by my teenage daughter, Geneva: “I’ve got a hankering to hike up the mountain today and do a POTA activation.” She replied, “I’ll need to pack my daypack and take the HT.” She was eager to see if she could communicate back to the house simplex with her mom and sis with her new FT-60R handheld.
My wife gave me her blessing, so I packed my trusty Red Oxx C-Ruck with my Elecraft KX2 kit, CHA Emcomm III Portable antenna, water, snacks, logbook and tablet, and used the ruck top flap to secure my three leg folding stool.
Pisgah Game Land WRC (K-6937) & Pisgah National Forest (K-4510)
We arrived at a suitable site about 40 minutes after leaving the QTH. My Garmin GPS and topo maps confirmed we were well within park boundaries. I found a rock outcropping and set up my station.
Even though the area was pretty dense with trees, Rhododendrons, and Mountain Laurel, I had no difficulty deploying the Emcomm III Portable antenna using my throw line.
That’s not a flying squirrel, it’s the winder/balun of the Emcomm III.
The Elecraft KX2 had no trouble at all matching the Emcomm III on all bands.
Even though Geneva was busy communicating with her sister (back at “Mission Control” via simplex) on the FT-60R, she actively logged all of my contact on the Surface Go tablet using N3FJP’s excellent contact log.
I quickly logged eleven contacts on 80 and 40 meters and my daughter suggested we cut the activation a bit short to take in more hiking.
We both wanted to follow a trail we found and see if it lead to the Blue Ridge Parkway.
Hazel has that “Seriously? You want to continue hiking?” look.
I packed up the station and hit the trail!
It turned out to be a good 45 minute trek along a ridge line increasing our elevation about 1,000′ (305M) ASL compared with home. The trail to the BRP was what I would call a moderately difficult trail (much easier than trail-blazing up the mountain!).
In the end, we found the Blue Ridge Parkway and the trail head to ascend Lane Pinnacle which is an excellent SOTA site. We decided to save Lane for another day this fall/winter with a very early departure from home.
Neva also discovered she could easily chat with her sister back at the QTH via 2 meter simplex at the parkway. This means I can definitely chat with the family back home when I eventually make that Lane Pinnacle SOTA activation.
The hike back to the POTA site was mostly downhill so only took about 40 minutes. I then veered off the path to trail-blaze our way back to the house. I did get a little off course which added about 25 minutes (!!) to our descent and requiring us to mitigate the steepest part of the ridge. Next time, I’ll pay more attention to my GPS map (although, in the winter, it’ll be much easier).
Still, it was a very enjoyable hike and certainly one of the more challenging I’ve been on in ages mainly due to the steep part at the end.
All-in-all: I discovered that there are no less than three POTA sites and one SOTA site within hiking distance of the QTH. The best part, by far, was the father/daughter time. Geneva is always up for an adventure (including currently studying for her General class license!).
Thursday, I set out to test how long the Icom IC-705 could operate during a Parks On The Air (POTA) activation with one fully-charged Icom BP-272 Li-ion battery pack. This, following my listening endurance test.
I knew conditions were pretty terrible Thursday in terms of propagation, but that didn’t really matter. I intended to call “CQ POTA” in CW until the ‘705 finally shut down due to low voltage. In my head, I imagined this wouldn’t take much longer than 1.5 to 2 hours and during that time, despite propagation, surely I’d work 10 stations to validate the activation, right–?
Sandy Mush Game Lands (K-6949)
I picked Sandy Mush Game Lands as my test site. Since I’d been there before, I knew there were ample trees to hang the Vibroplex EFT-MTR end-fed antenna, and I knew I’d likely be the only one in the parking area as this site is secluded and this was not a designated hunting day.
The Vibroplex/End-Fedz EFT-MTR antenna
Setup at the site was pretty straight-forward. I quickly deployed the EFT-MTR antenna–using my arborist throw line–in a “V” shape hanging over a high tree branch.
I picked the EFT-MTR because it’s resonant on my three favorite POTA bands: 40, 30, and 20 meters. Note that the IC-705 does not have an internal ATU.
Although I have an mAT-705 external ATU on loan to test, I didn’t take it to this first activation–I wanted to keep the set up simple for testing battery endurance.
On the Air
I started calling CQ at 16:30 UTC on the 40 meter band and set the IC-705 to beacon mode call “CQ POTA K4SWL.” No replies for 10 minutes. At that point, I discovered the POTA spots website was down for a scheduled upgrade (I have impeccable timing!), so I posted my spot on the POTA Facebook page.
Then my buddy Mike (K8RAT) sent a text message stating that the Reverse Beacon Network (RBN) had spotted me, but with a very low signal report. Hmmm….why would that be?
Note to IC-705 owners: zero watts is not zero watts!
I turned up the power to 5 watts (the max the IC-705 will achieve on a 7.4V battery pack) and was greeted by an instant CW pile-up.
What a blast! I started on 40 meters in CW, but eventually worked both 40 and 20 meters in SSB and CW. I then lowered the antenna, removed the SMA cap on the EFT-MTR coil, and worked 30 meters CW for the remainder of my time.
I logged my first contact at 16:28, my last at 18:18 UTC. So 1 hour 50 minutes of near constant operating.
Remaining battery capacity after 1:50 of operating.
The IC-705 battery pack was still going strong and had about 40% capacity left, but I simply ran out of time as I needed to run an errand in town, so had to shut down the radio and pack up.
I must admit: the IC-705 is doing a much better job managing battery usage than I would have expected. I’m guessing I could have operated for 3 hours or so at 5 watts without needing to recharge the BP-272 1880 mAh Li-ion battery pack.
I do believe I’ll invest in the larger BP-307 battery pack which has a capacity of 3100 mAh. It’s a pricey battery, though, at $130 US.
How does the IC-705’s battery endurance compare with the Elecraft KX2? I’m not sure yet, but I’m guessing the KX2 will have even better longevity as its current drain is less than half that of the IC-705. The KX2 will operate at 10 watts output for about 1 hour 15 minutes with the internal battery pack, before decreasing to 5 watts output. I’ve never tried a battery endurance test with the KX2 at only 5 watts.
Of course, with an external 12 volt battery, the IC-705 will pump out a full 10 watts of power as well.
Five watts and a wire–wow!
The biggest surprise of the day?
I worked stations from Oregon, and Saskatchewan to the Azores…in single sideband!
Here’s a map of my contacts–red signal paths are SSB, CW in green (click to enlarge):
This was one activation where 5 watts SSB actually snagged more DX than CW. Great fun!
While I’d like to think it was a little IC-705 “mojo” on its first field outing, in truth it had everything to do with the EFT-MTR antenna and what must have been a moment of propagation stability.
This was also my maiden voyage with the CW Morse Single Lever paddle. CW Morse sent this paddle, along with their double lever paddle and a selection of straight keys, for me to evaluate. If you’ve been considering an affordable, portable single-lever paddle, this is a brilliant one. I really enjoyed using it and the action is very easy to adjust.
I’m already regretting the decision to send it to my buddy Eric (WD8RIF) for a proper evaluation. (Just kidding, Eric! (Maybe.)) He only uses a single lever paddle for his numerous field radio adventures.
Eric will give this single-lever paddle a proper workout and give us a full report.
I must admit, I had a lot of fun with the IC-705/EFT-MTR antenna combo.
Of course, I’ll be taking the IC-705 to the field a lot in the coming weeks.
IC-705 Questions?
Feel free to comment and ask any questions you may have about the IC-705. I’ll do my best to answer them.
Practicing left hand lunching, right hand keying/logging!
It seems like lately I’ve had to work hard to log 10-15 contacts during my Parks On The Air (POTA) activations. Propagation has been so flaky, I use every trick in the book to snag at least my ten contacts for a valid activation: change antenna configuration, run up to 40-50 watts output, employ both CW and SSB, have friends spot me on the network, and try every band possible (typically from 80-17).
Note that the majority of my activations are proper QRP and rarely do I spend longer than 60 to 90 minutes actually on the air. Indeed, many of my activations are only 60 minutes long including set-up and take-down. That may seem short to most POTA folks, but that’s what works in my schedule and family life: quick hits. It’s one of the reasons I’m not more active in Summits On The Air (SOTA)–I need more time for those sites as they’re not as accessible as our numerous POTA entities.
Still, our local star has been misbehaving, and I had not planned to do an activation on Sunday (September 28) because I saw the propagation forecast and it was rather discouraging (A index 26, SW 505, Bz -2).
From home that morning, I chased a few parks but found it challenging to hear most of them. QSB was incredibly deep–strong stations gone in an instant.
Still, my wife suggested we take a picnic to one of our favorite local spots and how could I possibly visit a park without activating it? Right–?
Zebulon B. Vance Birthplace (K-6856)
What we, as a family, love about this site is the large covered picnic area and historic log cabins. Also, the site receives very few visitors on Sundays when the main museum is closed.
Each time we visit the Vance site, we bring my MSR liquid fuel stove and make lunch/dinner.
I set up the stove, got lunch started and my wife took over food prep.
Knowing propagation was unstable, I opted for more than QRP power this time–at least, at first–so I chose the Mission RGO One transceiver (capable of 55 W output) and CHA Emcomm III Portable antenna for this activation.
I deployed the Emcomm III in a sloping configuration with the end of the 73′ radiator high in a nearby (dead) tree and the counterpoise on the ground. I also suspended the winder/balun from the corner of one of the shelter’s rafter’s with paracord.
Since it’s difficult to see a wire antenna in photos, I’ve labeled the components in the following image (click to enlarge):
I didn’t know if this configuration would prove useful, but I knew it would be better than attempting this activation with my Wolf River Coils TIA vertical antenna.
I hopped on the air starting on 80M CW (at the request of my buddy WD8RIF), worked him and three stations in rapid succession. After a few minutes of silence, I moved up to the 40 meter band and worked 16 stations. I then moved to 30 meters and worked 11 stations.
I was working more stations than I would have ever guessed beforehand.
Since I only had about 10 minutes to spare after working 30 meters, I decided to plug in the microphone and work some park-to-park contacts. While I always intend to hunt for other parks while I’m in the field, more times than not, I don’t have the luxury of an Internet connection to check the POTA spots page like I did at Vance on Sunday.
I must say, I really love the CW Morse double paddles. They’re fully (and easily) adjustable, the action is responsive and smooth, and with the base, they’re incredibly stable on a hard surface. I highly recommend them.
At a setting like we had at Vance, I love the heavy base plate, but if I planned to hike into a site, I believe I’d remove the base to save on weight.
Unpredictable Propagation?
Perhaps there was a brief window of stability between solar events and I was able to take advantage of that while I was on the air? I’m not sure.
I never expected to log 37 contacts in the space of a little over an hour (with some of that time being off the air to help with picnic prep). Not on that Sunday when the solar numbers were in the dumps.
I’d like to believe it was a combination of things:
A large wire field antenna with decent gain and the ability to work multiple bands
40 watts of power (at first, I backed down to QRP on 30 meters)
Using CW for 34 of the 37 contacts
Perhaps unintentionally good timing
All I know is, I had a blast! It’s hard to beat a combination of good radio, good food, good scenery, and good weather!
I suppose this was also a lesson in simply hitting the field and ignoring the propagation.
Or as Rear Admiral David G. Farragut once famously said, “Damn the torpedoes, full speed ahead!”
Weather in North Carolina has been absolutely stunning over the past week, with the exception of two days where the remnants of Hurricane Sally dumped torrential rain. Two cold fronts provided us with gorgeous clear skies and dry conditions before and after Sally’s visit.
Of course, what better way to enjoy the outdoors than taking my radios to the field?
Last Wednesday, after several hours of knocking out home projects, my wife and I decided to enjoy the fall-like weather and get lost in Pisgah National Forest. My daughters were also keen for a little outdoor adventure, waterfalls, and hiking.
And our canine family member, Hazel? Always up for an outing!
“Let’s go, daddy!”
Of course, my wife was throwing me a bone as she knew I was chomping at the bit to try the new-to-me Chameleon Emcomm IIIantenna.
CHA Emcomm III antenna
Photo Source: Chameleon Antenna
I decided I’d pair the Emcomm III with the amazing Mission RGO One transceiver (a rig I’ll be reviewing in an upcoming issue of The Spectrum Monitor magazine).
Up to this point, I’d never used a Chameleon antenna in the field.
Chameleon Antenna kindly sent me both the CHA Emcomm III and CHA P-Loop a couple weeks ago for an honest field evaluation (and disclaimer: at no cost to me).
And being honest? The overall length of the Emcomm III wire antenna was intimidating. I’m used to field-ready wire antennas that are perhaps 30-41 feet in total length. The Emcomm III has a 73 foot long radiator and 25′ counterpoise! Holy smokes!
In my head, I imagined the only places I’d be able to use the Emcomm III would be in an open park with large, widely-spaces trees.
Turns out, I was wrong.
Two things make deploying the Emcomm III a breeze–even in the middle of a forest:
1.) An arborist throw line: this piece of kithas revolutionized my field antenna deployments. Not only does it give me the ability to suspend antennas much higher than I could before, but also to raise/lower antennas with ease compared with fishing line.
2.) The Emcomm III also has a floating dielectric ring on the radiator wire that allows you to create a suspension point. In fact, there are a number of ways you can deploy the Emcomm III which, I see now, makes it such a popular antenna among POTA operators.
To the field!
The first activation was actually a “two-fer”–meaning, two geographically-overlapping POTA park entities.
Wednesday, September 16: Pisgah National Forest (K-4510) & Pisgah Game Lands WRC (K-6937)
Propagation conditions on Wednesday were so crappy I found myself breaking with QRP to run 40 watts with the Mission RGO One into the Emcomm III. (The Emcomm III can actually handle up to 50 watts CW, 100 watts SSB.)
I first deployed the Emcomm III by pulling the radiator over a tree branch about 50′ high with the balun and winder near the ground. I then unrolled the counterpoise stretched out on the ground.
After only snagging about eight contacts in 50 minutes (a very meager amount for the typical park activation), I decided to re-configure the Emcomm III Portable so that it would act more like a NVIS antenna and perhaps grab a few regional hunters on 80 meters. There was no way I was leaving the forest without my 10 contacts to validate the activation!
I reeled in the radiator and re-attached my throw line to the floating loop and reconfigured the antenna to roughly match this “V” shape with a lower (roughly 25 ft) apex point:
NVIS “V” configuration (lifted from the CHA Emcomm III Portable product page)
I used the RGO One’s internal ATU to match the 80 meter band 1:1.
I started calling CQ on 80 meters CW and, evidently, the POTA site auto-spotted me via the Reverse Beacon Network (RBN) because within a minute, I found myself at the other side of a mini pile-up! I very rapidly worked 8 stations–most of them were in nearby Tennessee. These were callsigns I was not used to logging because typically they’d be under my skip zone–a little too local.
It was nice to get solid copy on 80 meters without the deep QSB on 40, 30 and 20 meters.
The thing that struck me about the Emcomm III at this first activation was how easy it was to reconfigure in the field despite the lengthy radiator. The wire is Copper Clad KEVLAR PTFE (Telflon-coated) and doesn’t easily tangle. It slides so easily through the trees–there’s no coil or bulky bits to get caught in the limbs.
When packing up, it wraps around its built-in winder very easily. Kudos to the designer.
Saturday, September 19: Pisgah National Forest (K-4510) & Pisgah Game Lands WRC (K-6937)
Last Saturday, I wanted to try the CHA Emcomm III in a different region of Pisgah National Forest and see how well it might pair with my Elecraft KX2.
We found an ideal spot to set up: a forest service road that had obviously been closed the entire season.
I deployed the Emcomm III Portable in the same “V” configuration as I did during the first activation, but this time raising the apex of the “V” up to 45 feet.
It’s important to note here that being a random wire antenna, the Emcomm III relies an an ATU to get good matches on each band. The Mission RGO One’s internal ATU did a brilliant job finding matches and, turns out, my KX2 did as well.
In fact, before I started calling CQ, I moved across the bands to see if I could get good matches with the KX2 ATU. From 80-20 meters, I think the highest SWR I had was 1.3:1. (The KX series ATU is truly a benchmark in my book!)
That day, even though the weather was gorgeous, propagation was terrible. I read a few reports from experienced POTA and SOTA folks who couldn’t snag the needed 10 contacts for a valid activation earlier that day. There were contests and QSO parties on the bands so lots of signals–but more than once on the phone portion of the 40 meter band, I could hear two stations calling CQ on the same frequency and trying to work the same stations totally unaware of each other. Not a good day to play radio in the field and was starting to wonder if I could even snag my needed ten contacts.
Turns out, I had nothing to fear.
Since I could, quite literally, pick any band the KX2 could transmit on, I was able to float across the HF spectrum, call CQ, and the RBN would make sure I was spotted properly to the POTA network.
Getting that first ten is a great feeling!
I pretty effortlessly snagged my ten, and then a number to boot.
When I seek a spot to set up in a national forest, I often look for forest service roads with locked gates. When I set up on an unused road, it typically means I’ll have a high branch to hang the antenna and also a little space to deploy it without touching other trees. Our spot on Saturday was ideal.
Again, hanging and deploying the Emcomm III was effortless. I did bring about 12 feet of paracord with me this time allowing me to tie off the end of the radiator if I chose the “V” shape.
Monday, September 21: Mitchell River Game Land (K-6926) & Stone Mountain State Park (K-2754)
Monday was another stunning weather day.
I decided I wanted to finally make a pilgrimage to an ATNO (All Time New One) POTA site I’d been eyeing for a few months: Mitchell River Game Land.
Because propagation was fickle and this site was a good 3 hour round trip from where I was staying with family, I planned to use the Mission RGO One and run 40-50 watts or so.
However, when I got to the site, I realized I’d left the RGO One’s power cable at home. Fortunately, I still had my Elecraft KX2, so 10 watts would have to do.
I found a large parking pull-off area surrounded by trees. There was a ton of room to deploy the Emcomm III.
I decided to extend the radiator in a sloping configuration and elevate the 25 foot counterpoise.
The configuration was Identical to the one above , but the balun/center winder and counterpoise were suspended about 4 feet off the ground.
I fired up the KX2 and started calling CQ on 80 meters. The RBN picked me up and the POTA site auto spotted me. In a couple of minutes, I snagged my first three stations, then I heard no other calls, so moved up to 40 meters where I worked a big pile-up of stations. It felt like a mini-DXpedition at times. I loved it!
I even hopped on the phone portion of the 40 meter band and worked a few stations, getting respectable signal reports despite unstable propagation.
This activation went so well and the weather was so ideal, I decided to fit in another park that was only a 30 minute drive and was new to me: Stone Mountain State Park.
The thirty minute drive was relaxing and reminded me how much I enjoy this portion of the NC foothills leading up to the Blue Ridge Parkway and escarpment.
By the time I reached the park it was 1:30 pm on a Monday and I essentially had the place to myself (even though in my head I was preparing for crowds).
I had my pick of picnic spots so I found the one with the highest branches. One shot with the arborist throw line and I snagged a branch that must have been 45-50 feet high.
I first deployed the Emcomm III by simply running the radiator over a tree branch and laying the counterpoise on the ground–much like I did in the first Emcomm III activation and deployment.
I started calling CQ and worked about 4 stations, then nothing. The bands simply died on me!
After 30 minutes, I reconfigured the Emcomm III into a similar “V” shape I used at Pisgah National Forest with the apex at about 40 ft and the center winder and counterpoise elevated about 3 feet.
After some persistence, I finished off my ten contacts and then packed up–I spent about 70 minutes on the air and needed to grab lunch!
I honestly believe I would have found this activation even more challenging if I didn’t have an antenna that could snag stations on the 80 meter band since it was in the best shape that afternoon.
Again, I was very impressed with how easy it was to reconfigure the Emcomm III.
Tuesday, September 22: Tuttle Educational State Forest (K-2754)
After staying two nights with my parents in the Piedmont of North Carolina, I made my way back home to the mountains Tuesday afternoon. Again, the weather lured me back out to make just one more activation! (Let’s face it: the weather is a bit of an excuse).
One of my favorite parks that’s only a 20 minute detour off my path is Tuttle Educational Forest. It’s never busy there and they have a large picnic area with ideal trees for hanging antennas.
After searching through my main field pack (a Red Oxx C-Ruck), I found a spare power cord that would work with the Mission RGO One transceiver.
I didn’t have a microphone, though. That’s okay: it would be a CW-only activation.
Although I had the park to myself, I didn’t want to take up a large portion of the picnic area by deploying the Emcomm III in a sloping configuration similar to my activation at Mitchell River. I decided, instead, to be space efficient and use the “V” configuration once again with the apex at about 35 feet and the counterpoise on the ground. By doing this, the antenna footprint could almost fit within my picnic table area (although my counterpoise did snake into the woods).
I can’t remember how long I was on the air, but I do remember it was a breeze logging contacts that afternoon. Very enjoyable. I do love the Mission RGO One–the receiver is amazingly quiet, sensitive, selective, and signals simply pop out of the ether. It also sports silky-smooth QSK. Again, although I’m 90-95% a QRPer, it’s nice to push the juice a bit when propagation isn’t kind. The RGO One will push 55 watts.
The Mission RGO One ATU also snags excellent SWR matches across the band with the Emcomm III.
Emcomm III initial impressions
This past week, I gained some serious respect for the Emcomm III.
What impresses me most is its versatility and robust quality.
Don’t get me wrong: it’s not a magic antenna or anything. It’s essentially a random wire antenna.
What makes it such a fabulous field antenna, though, is its configurability. That and its uncompromised military-grade construction.
I shouldn’t have been so concerned about the radiator length as it’s actually pretty easy to accommodate and helps make this an efficient antenna on the low bands. (Look for me activating parks on 160 meters this winter!)
I believe I can deploy the Emcomm III anytime I have a half-decent tree nearby. I believe I could also use my 31′ Jackite fiberglass pole to extend one end or even the middle of the antenna if I wanted to go NVIS, but I would have to be careful to accommodate strain relief since the Emcomm III Portable is made of heavier materials than my EFT Trail-friendly antenna, for example.
I’m not sure I’d ever reach for the Emcomm III for a SOTA activation when I’d need to take a close look at weight and size. But for POTA? It’s brilliant. And, of course, for emergency communications (as the model name implies). The Emcomm III would also be an excellent addition to a radio club’s antenna arsenal.
The Emcomm III, like all Chameleon products, is designed and made in the USA. Since they use military-grade components, you pay a premium. The Emcomm III is one of their least expensive products at $139 US. Is it worth the price? Absolutely. In fact, I’m thinking about buying a second one to keep in my camper.
Thank you, Chameleon Antenna, for sending me the Emcomm III Portable for a proper field evaluation. I’d also like to thank Chameleon Antenna for agreeing to be a sponsor of QRPer.com!
Note: the following post originally appeared on our sister site, the SWLing Post.
The Par EndFedz EFT-MTR triband (40/30/20M) antenna
In July, I purchased a tiny QRP transceiver I’ve always wanted: the LnR Precision MTR-3B. It’s a genius, purpose-built little radio and a lot of fun to operate in the field.
It’s also rather bare-bones, only including a specific feature set built around ultra-portable CW operation.
While the MTR-3B has features like CW memory keying, a wide operating voltage (6-12 VDC), extremely low operating current (20 ma in receive), real-time 24 hour clock, and a full compliment of keying adjustments, it lacks other features like a volume control, SWR meter, speaker, and built-in antenna tuner.
Some of those may seem like big omissions but SOTA and POTA activators who like extremely lightweight/portable gear love the MTR-3B for being so purpose-built.
The MTR-3B (and its predecessors) operate on three bands: 40, 30, and 20 meters. These are, without a doubt, my favorite bands when operating portable since antenna lengths are reasonable.
Since the MTR-3B doesn’t have an internal ATU, you need to pack an external tuner or, better yet, a resonant antenna–ideally, one that can be used on all three bands.
Although many of my portable transceivers have built-in ATUs, I rarely use them because I primarily operate with resonant antennas. Resonant antennas are more efficient–giving you the maximum mileage per watt. In addition, they’re also more simple: connect them to the rig and hop on the air. No tuner or tuning required.
The EFT Trail-Friendly antenna is incredibly compact and quite easy to deploy.
I’ve mentioned in previous posts that I’m a big fan of the Par EndFedz Trail-friendly EFT tri-band antenna (above) which is resonant on 40, 20, and 10 meters. I’ve activated well over 130 parks with this little antenna.
After I took delivery of the MTR-3B, I borrowed the Trail-friendly EFT antenna from my KX2 field kit. It worked well on 40 and 20 meters, but it doesn’t cover the 30 meter band. Also, by borrowing the EFT from the KX2 kit, I broke one of my rules: never borrow from one field kit to feed another. This led to me leaving the EFT hanging in a tree at a remote park and returning a week later–a three hour round-trip(!!!)–to retrieve it. (FYI, in all fairness, I also blamed my trusty canine companion for this mishap!)
I was very pleased with this decision as I’m guessing LnR Precision wanted to hand off antenna production so they could focus on the very popular Mountain Topper transceiver line.
Vibroplex is owned by my buddy, Scott Robbins (W4PA), who is not only a successful entrepreneur, but also an award-winning contester and DXer. I’ve known Scott for years and knew he’d not only be a great steward of the Par product line, but also push new innovations.
I emailed Scott asking if Vibroplex had a field-portable antenna that would be resonant on 40, 30, and 20 meters. Turns out, there’s a Par antenna designed specifically to pair with the MTR-3 series transceivers: the Par EndFedz EFT-MTR.
The new EndFedz ® EFT-MTR is a 40m/30m/20m tri-band QRP antenna rated up to 25 watts. The “MTR” name was selected as LNR Precision developed this antenna to be the perfect companion to the wildly popular 40/30/20m Mountain Topper QRP transceiver. The EFT-MTR’s total length is 65′ of 22 AWG polystealth wire and weighs less than 4 ounces! It is built with the same high level of workmanship and quality that you have come to expect with all EndFedz ® antennas.
A particular innovation on this antenna: This EndFedz is a little different than previous designs. The user has the option to remove an SMA connector at the end of the 30M resonator to enable just 30 meters, or keep the SMA installed for 40 and 20 meters. Because of the broad bandwidth of the antenna, it is unlikely that it will require tuning in the vast majority of deployments. This is particularly true of 30 meters where the band is very narrow. As our tagline states, “They Just Work!”
Included with the EFT-MTR is the EndFedz Antenna Winder. Conveniently allowing winding up the antenna line to not have a tangled mess at the end. The winder will hold both the antenna and 25 feet of RG-174U coaxial cable (optional accessory).
Scott offered to send me an EFT-MTR to evaluate in the field (disclaimer: at no cost to me) and I accepted without hesitation, of course!
An EFT-MTR field review
I’ve taken the EFT-MTR antenna to three park activations at this point and have formed some opinions about it.
The EFT-MTR fits perfectly in a slide-in pocket in the main compartment of the Boot Boss.
First of all, I couldn’t be more pleased with the size as it fits perfectly in my MTR-3B field kit built around my Red Oxx Booty Boss pack.
I really like the built-in antenna winder: it’s larger than that of the EFT Trail-Friendly, but also much easier to wind up and manage post-activation.
I’ll admit, the length of the EFT-MTR was a bit surprising the first time I deployed it: 65 feet. Keep in mind, though, I had been used to a much shorter 41 foot radiator on the EFT Trail-friendly. Occasionally, I operate in spots where I simply don’t have the room to deploy a long antenna. I also worried that the EFT-MTR resonance might be negatively affected by winding its way through trees and over a branches. The MTR-3B transceiver does not like high SWR values and has no built-in SWR meter to monitor it. Last thing I wanted to do was harm the MTR finals.
You might be able to spot the feed point of the EFT-MTR at my activation of K-6952 this week.
Fortunately, winding its way through trees doesn’t seem to have a significant impact on SWR.
Each time I’ve taken the EFT-MTR to the field, I’ve also taken my KX2 which I’ve used to read the antenna’s SWR value. So far, the difference has only been negligible and SWR well within the tolerances of the MTR-3B. Score!
I should note here that since I’ve started using an arborist throw line, I’m also able to hang antennas much higher than I could before. This has had a huge impact on all of my field activities.
Removing the SMA cap changes the EFT-MTR from a 40/20 to a 30 meter resonant antenna.
To be resonant on 40, 20 and 30 meters, the EFT-MTR requires a field modification. On the coil about 2/3 the way up the antenna, there’s an SMA connector with a small screw on cap (see above). When the cap is on (thus completing the connection) the antenna is resonant on 40 and 20 meters. You must remove the cap for it to be resonant on 30 meters.
Since I’ve been using the EFT-MTR, I start an activation on 40 meters (which is typically my most productive band), then move to 20 meters (typically, my least productive). If I have the time, or need the extra contacts to confirm a valid activation, I lower the antenna, unscrew the SMA cap, and raise the antenna again.
I thought at first this would be a major pain, but it hasn’t. Now that I’m using an arborist throw line, it’s super easy to lower and raise antennas. But even when I’ve used fishing line, it really hasn’t been an issue.
The only issue I see is I’m afraid I’m going to lose that little SMA cap in the field. To prevent this, I’ve made it a routine to immediately put it in the internal zippered compartment of the Booty Boss pack. I might find a source for those caps, though, just in case I still lose this one.
I’ve been very pleased with the EFT-MTR’s performance. I’m guessing it’s actually higher gain than my beloved EFT Trail-Friendly antenna. On my last activation with the EFT-MTR, I knocked out eight 40 meter contacts in about eight minutes during a period of poor propagation. Note that the MTR-3B was only pushing 3 or 4 watts of power.
I then moved to 20 meters where, frankly, propagation was so crappy I didn’t hang out there long. Instead, I lowered the antenna, removed the SMA cap, and started calling on 30 meters. Within a few minutes, I racked up the rest of my contacts.
I was very pleased with how quickly the Reverse Beacon Network picked up my CQs and was thus auto-spotted on the POTA website.
Conclusion?
If you own a Mountain Topper MTR-3 series transceiver, I highly recommend the EFT-MTR antenna. As with my EFT Trail-friendly and Par sloper, the quality is top-shelf. I expect the EFT-MTR will last even longer than the EFT Trail-friendly since the winder is so accommodating and the in-line coil is designed so that it doesn’t snag on branches as easily.
I’m looking forward to much more field fun with the MTR-3B and EFT-MTR combo!
At least 95% of the time I’m playing radio in the field, I use wire antennas and suspend them in trees.
Since I do a lot of park activations for the POTA program, trees are typically very easy to come by and most of the time the park office doesn’t care if I hang an antenna in their tree for a couple of hours.
For years, I’ve been using a heavy steel nut–a nut that would fit a very large bolt–as a weight and attach it to fishing line. I then simply throw the nut into a tree and pray the fishing line deploys properly. I have reasonably good aim, so–on a good day–I typically only need one or two throws/tries to get the fishing line over a branch. On bad days? Well… let’s just not talk about that.
There are some inherent weaknesses in the fishing line/monofilament system:
First of all, I’m lobbing a heavy metal object into the trees. If it ricochets–and it eventually will–it can come back down to earth and land where you might not want it to (for example, on your radio, on your car, or on your friend’s head). Fortunately, I’ve never hit anything or anyone as I’m careful to clear the area first, but unfortunately, I once had the nut hit a tree and come back down near me. That was a little scary.
Secondly, fishing line isn’t exactly recyclable and you simply can’t use it over and over. I get at most three deployments with a section of fishing line before it gets too stretched and unworkable.
Finally, fishing line is incredibly prone to tangle, especially near the end of the spool.
A Better Solution? The Arborist’s Throw Line
The arborist throw line is no recent innovation. For years, I’ve read recommendations from other ham radio operators who swear by arborist throw lines but I only recently decided to take the plunge after one very frustrating park activation where my fishing line knotted and almost got permanently stuck in a gorgeous tree. I’m very much a “Leave No Trace” kind of guy, so I was incredibly relieved when I was finally able to work the fishing line out of the tree.
I once talked with an arborist about throw lines and he stressed the importance of getting not just the line, but also a throw line storage cube. The cube allows you to both deploy and take up the line without any tangles or knots.
All in, I spent about $50.00 US for both.
Preparing the throw line
My arborist buddy gave me an important tip: the throw line needs to be stretched.
As you can see in the photo above, the throw line is packed in a bundle that’s easy to unroll. After you unroll it for the first time, though, the line has a “memory” of all those bends from its life in the package.
You can remove much of the throw line memory by tying one end of the line to a tree and stretching the line to its full length. The line is 150 (or so) feet long, so you’ll need an open space to do this.
The arborist in this video shows how this is done (I’ve queued it to the point in the video where he shows how to do this):
Knots
You’ll need to attach the throw line to the throw weight, of course.
There are a number of knots arborists use, but I’m a fan of the slipped simple noose knot. Perhaps it’s because it’s easy to tie even with semi-rigid line, it holds quite well and, most importantly, it’s easy to untie.
Looks like arborists use it too because when searching for an instructional video, the first result was from an arborists’ channel:
Throwing up!
There are a few different ways to launch a throw line into a tree.
Take my advice here: practice at home before you hit the field! It could save you a lot of embarrassment, although, admittedly, my at-home practice sessions gave my wife and my daughters good reasons to chuckle.
I’ve only been using the throw line for a little over a week, so I’m still sorting out which method works best for me. One thing I discovered very quickly, though: no matter which launch method I use, I can send that throw weight into a tree at least 60% higher than I could before.
No doubt, the throw line and weight really put the laws of physics in your favor!
Here’s a great video highlighting different throw line launch techniques:
In practice
I took the throw line to the field today for the first time and I’m very pleased with how effectively it works.
I was able to place my antenna on a much higher branch than I could have otherwise. It took me three tries today, but it had more to do with my poor aim. As with any skill, this will, I think, improve with practice.
The storage cube folds down flat and keeps the line from tangling
Besides the improved antenna height, I love that the line can be used over and over again. Also, it’s strong enough that should it ever get caught in a tree, I can pull it out without the line breaking.
I can also reel in the line at least three or four times faster than I could with fishing line. Simply flake it into the storage cube one foot at a time.
When the line has been stored along with the throw weight, you can fold the storage cube down flat, then fold and secure it into a compact triangle.
Are there any negatives with the throw line system? Here are a few I’d note:
Bulk. Even when packed down, the line in the storage cube take up much more space than fishing line. Although it easily fits in even my smallest backpack (the GoRuck Bullet), I’m not sure I’d take it on a long hike.
This system requires a little practice and skill–you can’t pull it out of the package for the first time in the field and expect perfect line launches.
The throw line is more conspicuous than fishing line. If you’re trying to be a bit stealthy–as many of us are these days during the Covid-19 pandemic–the bright yellow throw line will attract more attention and questions from other hikers/campers, etc.
One happy activator!
Even though it’s bulky by my standards, I see the throw line becoming a permanent part of my field kit and I expect I’ll use it on most of my POTA activations.
Have you been using a throw line to hang field antennas? Or do you use a different system? Please comment!
This past week, I hit the parks pretty hard while giving the lab599 Discovery TX-500 a good field evaluation. I managed to activate eight parks in the seven days I had the radio.
It was so much fun.
Today, I was going through my logs and was reminded of one park activation on the Blue Ridge Parkway in particular…
The activation was a bit impromptu (like most of my activations, if I’m being honest). My family packed a picnic, I grabbed the TX-500 from the workbench, and we headed to the parkway.
I set up the station on a picnic table and deployed my trusty EFT Trail-Friendly 40/20/10 meter end-fed antenna. I started calling “CQ POTA” on CW and within 15 minutes or so amassed the 10 contacts I needed to validate the activation. Signal reports were overall a little on the weaker side, but propagation that day wasn’t exactly stellar. I worked a few more CW stations, then switched to SSB.
I started my SSB run by trying to work a few “Park to Park” sites because my phone managed to load a list of POTA spots from my very dubious mobile phone connection. I heard a strong signal from a park and replied, “K4SWL, Park to Park, Park to Park!” No reply.
Typically, when you say “Park to Park” an activator makes your contact their high priority. So I was a bit shocked not to hear a reply. I tried again. Nothing.
Then I cycled through some of the radio settings and discovered I had left the radio set to one watt of output power. Earlier that day while testing the TX-500 in the shack, I checked output power levels by hooking it up to a watt meter and dummy load. I forgot to move it back up to 5 or 10 watts.
No wonder I was so weak on SSB! I increased power output to 10 watts (the TX-500 max output) and quickly confirmed that other park.
I worked a few more SSB stations, then packed up for the day.
When I got back home, I made a little map of my contacts.
On the map below, all of the green pins below were CW contacts and made with one watt of power. The red pins are SSB contacts with 10 watts. The yellow star is roughly my location:
I operate QRP (or, at least 12 watts and below) 95% of the time I’m on the air. On rare occasions, I’ll run up to 50 or possibly 100 watts. Besides the amazing portability QRP rigs offer, it’s so much fun to travel the airwaves on peanut power–whether I know it or not.
But I’m pretty sure I’m preaching to the choir here, right–?
I know this: there’s magic in one watt and a wire!
Over at our other radio blog, the SWLing Post, I’ve been publishing reports and videos of the lab599 Discovery TX-500 general coverage QRP transceiver. If you haven’t been following those posts, you might like to check out the following articles in particular:
I received my Mountain Topper MTR-3B last week, and I’ve already taken it on a POTA activation.
Last weekend, I decided to break it in on a POTA “two-fer” site: Hampton Creek Cove State Natural Area (K-6246) and The Overmountain Victory Trail (K-4577) in Tennessee. Hampton Creek Cove was actually an ATNO (all time new one) so it was a trial by fire!
In short, the MTR-3B was marvelous. I’m so impressed.
As I mentioned in a previous post, I’m building a full SOTA/POTA activation kit for the MTR-3B. I already have a kit built around my KX2 and I don’t want to “borrow” any items from it (so I’m not surprised later in the field when an item is missing).
The TalentCell Rechargeable 12V 3000mAh Lithium Ion Battery Pack is the little black box.
I also used my Whiterook paddle (which needs new paddle arms at this point) but that will soon be replaced with a set of N0SA portable paddles I recently ordered.
Since the MTR-3B has no volume control, I used a pair of 20 year old Sennheiser earphones I bought when I lived in Munich. These have been in a drawer for ages because I now prefer using in-ear earphones with silicon earpieces for better comfort and sound isolation. But the Sennheisers have one thing none of my other earphones sport: in-line volume control.
While the earphones worked well for this activation, I’d still prefer a set of in-ear earphones with in-line volume control. Any suggestions from MTR-3B owners? Also, I’d like a compact amplified speaker with volume control to carry as an option when needed. If you can recommend one, please comment!
I’m writing an article for The Spectrum Monitor magazine about portable power later this year. I noticed that a number of MTR-3B owners swear by 11V rechargeable cells that are used in the RC and drone markets. Many have a similar compact form-factor as the common 9V battery. I understand, however, some of these cells need special chargers and equipment to balance them.
I would appreciate any and all information about these batteries.
In the meantime, Rich (N8TGQ), recently shared a pic of his Mountain Topper portable pack. Check it out:
I think it’s brilliant how he’s mounted everything on a compact plastic cutting board inside the case. Rich says that what he loves about this set-up is that everything is there, ready to go–simply plug in the antenna!
I love seeing how others build out their field kits! Please comment or contact me if you’d like to share yours here on QRPer.com!
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What I like about this particular POTA site is the open parking area which allows me to configure the Emcomm III a number of ways.
I’m guessing the apex of the antenna was easily 45′ high.
After working a few stations on 80 meters, I decided to test the mAT-Tuner over a fairly wide frequency range before calling CQ on the 40 meter band.
